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Experimentelle und numerische Untersuchungen zur Dispersion von Dichteströmungen in einem stochastischen ModellaquiferStarke, Bettina Unknown Date (has links)
Univ., Diss., 2005--Kassel
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An exploration of the activation of sympathy in relation to economic inequality and the poorRemillard, Christopher 07 November 2018 (has links)
As economic inequality in the United States continues to increase, the ways in which Americans cope with and conceptualize the issue itself as well as the disadvantaged groups affected by it has become increasingly salient features of their political attitudes. While important research has been done, particularly by Bartels (2009), showing that Americans share widespread consensus that economic inequality is a negative feature of American society and that Americans do not harbor any innate antipathy towards the poor, more work needs to be done to understand what activates Americans’ sympathy for the poor. This study, building on Burden and Klofstad’s (2005) assessment into the effects of cognitive and affective priming, seeks to understand how issue and subgroup framing alters political expression. I find that the use of the word “feel” in survey questions—as opposed to the word “think”—makes respondents more likely to hold poor subgroups less accountable for their economic circumstances. However, this differential outcome does not manifest when applied to policy-based questions. This indicates that invoking person- or group-based arguments along with affective signifiers shows the best promise for activating sympathy for the poor among Americans.
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Factors of Process Model Comprehension - Findings from a Series of ExperimentsMendling, Jan, Strembeck, Mark, Recker, Jan 14 January 2012 (has links) (PDF)
In order to make good decisions about the design of information systems, an essential skill is to understand process models of the business domain the system is
intended to support. Yet, little knowledge to date has been established about the factors that affect how model users comprehend the content of process models. In this study, we use theories of semiotics and cognitive load to theorize how model and personal factors influence how model viewers comprehend the syntactical information of process models. We then report on a four-part series of experiments,
in which we examined these factors. Our results show that additional semantical information impedes syntax comprehension, and that theoretical knowledge eases
syntax comprehension. Modeling experience further contributes positively to comprehension efficiency, measured as the ratio of correct answers to the time taken to provide answers. We discuss implications for practice and research.
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Květinové záhony z přímých výsevůNovosadová, Vladěna January 2015 (has links)
The dissertation dealt with sowing annuals in the establishment of flowerbeds from direct sowing of taxon which are potentially suitable for autumn and spring sowing. In the experimental part was attempted to annuals of direct sowing. There were realized three sowings, in autumn 2013 and 2014 and in spring 2014, when were sown 26 same taxon of the seed. The aim of the experiment was evaluated the germination of seeds, height and flowering taxon, aesthetic effect of fetus, effect of taxon in the composition and suitability growing and seeding taxon. Based on all these results there were performed the comparison and evaluation and the conclusions and recommendations were defined for following experiments and practice. After evaluation all the results, interesting and perspective annuals for directautumn sowing appeared Ammi visnaga (L.) Lam., Bupleurum rotundifolium L., Clarkia pulchella Pursh. 'Mix', Consolida ambiqua (L.) P. W. Ball & Heywod. 'Hyacintokvětá', Nigella damascena L. 'Cramer s Plum', Nigella orientalis L., Papaver rhoeas L. 'Shirley Double Mixed'. There were evaluated the best and the most perspective annuals for direct spring sowing - Borago officinalis L., Bupleurum rotundifolium L., Calendula officinalis L. 'Pacific Beauty Směs', Consolida ambiqua (L.) P. W. Ball & Heywod. 'Hyacintokvětá', Cosmos bipinnatus Car. 'Sonata', Cosmos sulphureus Car. 'Redcrest', Nigella damascena L. 'Cramer s Plum'..
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Domácí experiment při výuce fyziky na ZŠ / Home experimemt by physics education at basic schoolsMARTÍNEK, Pavel January 2012 (has links)
This diploma thesis deals with home preparation for teaching physics at basic school by simple experiments. Set of worksheets with didactic analysis and evaluation of a questionnaire survey of attitudes pupils and parents of this theme. The worksheet is possible use in education of physics on basic school. Conclusions of questionnaire survey give an answer about appropriateness of home experiment by physics education from the perspective pupils and parents.
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Návrh soupravy pomůcek pro výuku fyziky na ZŠ / The concept of aid set for physics education at basic schoolVRKOČ, Pavel January 2012 (has links)
Abstract This dissertation is thematicly focused on oscillation, wave and acoustics. The goal of this work is to certified suitability of experiments in the physics lessons on the elementary school. There are different kinds of experiments, which are suitably put into lessons. These experiments help pupils to understand the subject matter. A part of the work is also draft of kit to demonstrate experiments which are carrying out during the physics lessons. The dissertation contains a set of experiments with this kit. To check out precondition, that putting experiments is suitable activity during the lessons are here suggested and in practice verified worksheets. The analysis of these worksheets is the conclusion of this dissetation.
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Análise teórica e experimental sobre incandescência em espécimes de madeiraRabelo, Elaine Reis de Carvalho [UNESP] January 2003 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:35:41Z (GMT). No. of bitstreams: 0
Previous issue date: 2003Bitstream added on 2014-06-13T20:46:44Z : No. of bitstreams: 1
rabelo_erc_dr_guara.pdf: 6183140 bytes, checksum: d7bd9eecbf970b1f0de95902bb7fa5b8 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Este trabalho trata da combustão sem chama, denominada incandescência, em espécimes de madeira. O estágio de incandescência é muito comum em queimadas florestais, ocorrendo após o período de chamas, quando a biomassa de tamanho maior permanece fumegando por até vários dias. Este material, em estado de incandescência, é foco permanente de emissão de gases tóxicos bem como de re-ignição de biomassa não queimada. Os objetivos principais do trabalho são: verificar experimentalmente os parâmetros que favorecem o início e a continuidade do processo de incandescência e quantificar as concentrações de CO, CO2, O2 e HC durante a queima. Também serão determinadas temperaturas, em diferentes pontos dos corpos de prova, a velocidade da frente de incandescência e, finalmente, a taxa de queima. Os ensaios foram feitos em um forno de 1,80 m de comprimento por 0,60 m de diâmetro, conectado a um controlador de temperatura, com vazões de ar de combustão previamente estabelecidas. Além da vazão de ar, outros parâmetros também variaram, como a temperatura interna do forno, a espécie da madeira, o volume e a umidade da amostra. Para otimizar a execução dos testes foi aplicada a técnica de Projeto de Experimentos. Os ensaios de laboratório foram comparados com os resultados obtidos em uma queimada realizada no interior da floresta Amazônica, no norte do estado de Mato Grosso. / This work investigates non flaming combustion in biomass logs. The process is called smouldering combustion. The occurrence of smouldering is very common in forest fires, where the large sized biomass remains fuming for several days. The material in the state of is a source of toxic gases and of ignition for unburned biomass. The main goals of the work are experimentally check the parameters that favor initiation and permanence of the smouldering process and measure CO, CO2, O2 and HC concentrations during the burning. The velocity of the smouldering front was determined by thermocouples placed in different points of the biomass sample. The average burning rate was also determined. The tests were performed in a furnace of 1.80 m length by 0.60 m diameter. A temperature controller was used to set the desired furnace temperature. The mass flow rate of air was controlled by valves and measured with rotameters. Tests were conducted for different biomass species and sample volumes and moisture contents. To optimize the number of tests the technique Project of Experiments was applied. Results of the laboratory tests agreed well with those obtained in the Amazon forest, in the north of the state of Mato Grosso, Brazil.
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On lower bounds of mixture L₂-discrepancy, construction of uniform design and gamma representative points with applications in estimation and simulationKe, Xiao 13 May 2015 (has links)
Two topics related to the experimental design are considered in this thesis. On the one hand, the uniform experimental design (UD), a major kind of space-filling design, is widely used in applications. The majority of UD tables (UDs) with good uniformity are generated under the centralized {dollar}L_2{dollar}-discrepancy (CD) and the wrap-around {dollar}L_2{dollar}-discrepancy (WD). Recently, the mixture {dollar}L_2{dollar}-discrepancy (MD) is proposed and shown to be more reasonable than CD and WD in terms of uniformity. In first part of the thesis we review lower bounds for MD of two-level designs from a different point of view and provide a new lower bound. Following the same idea we obtain a lower bound for MD of three-level designs. Moreover, we construct UDs under the measurement of MD by the threshold accepting (TA) algorithm, and finally we attach two new UD tables with good properties derived from TA under the measurement of MD. On the other hand, the problem of selecting a specific number of representative points (RPs) to maintain as much information as a given distribution has raised attention. Previously, a method has been given to select type-II representative points (RP-II) from normal distribution. These point sets have good properties and minimize the information loss. Whereafter, following similar idea, Fu, 1985 have discussed RP-II for gamma distribution. In second part of the thesis, we improve the discussion of selecting Gamma RP-II and provide more RP-II tables with a number of parameters. Further in statistical simulation, we also evaluate the estimation performance of point sets resampled from Gamma RP-II by making comparison in different situations.
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A mecânica da fratura elástica linear e o modelo coesivo na previsão do fraturamento de rochas / The linear elastic fracture mechanics and the cohesive crack model in predicting the fracturing of rocksDaniela Gírio Marchiori 22 August 1997 (has links)
O presente trabalho foi desenvolvido com o intuito de verificar a influência do efeito escala na variação da forma da curva tensão-deformação e na resistência de duas rochas brasileiras: o arenito silicificado da Formação Botucatu e o basalto da Formação Serra Geral. Para tanto, foram executados ensaios de flexão a três pontos, com controle do processo de fraturamento, em amostras de ambas as rochas. Os ensaios foram conduzidos sobre quatro tamanhos diferentes de corpos de prova. Experimentalmente, não foi observada variação na forma da curva força-deslocamento com o tamanho das amostras. Observou-se também que a variação da resistência em função dos tamanhos das amostras aproxima-se do previsto pela Mecânica da Fratura Elástica Linear. As curvas força-deslocamento obtidas experimentalmente foram comparadas com duas outras curvas obtidas numericamente, uma através de simulações baseadas na Mecânica da Fratura Elástica Linear, e outra com base na teoria do Modelo Coesivo de propagação de fraturas em análise não linear. Os dados obtidos mostram que entre as duas simulações numéricas a que apresenta melhor aproximação à simulação experimental é a do Modelo Coesivo e que ambas subestimam os deslocamentos no trecho pós-ruptura dos ensaios. / This present work has been developed aiming to verify the scale effect influence on the stress-strain curve form as well on the strength of two Brazilian rocks: Botucatu sandstone and basalt from Serra Geral Formation. Using samples of those rocks three point beam bending experiments have been made in with the crack displacement opening mouth was controlled. The experiments have been conducted using four different samples size. In the experiments no variation in the form of the force-displacement curve has been observed considering those chosen samples sizes. The rock strength variation for those samples is approximately the one predicted by the Linear Elastic Fracture Mechanics Theory. The force-displacement curves experimentally achieved were compared with two other curves obtained numerically, one using the Linear Elastic Fracture Mechanics Theory with FEM and other assuming the fictitious Cohesive Crack Model with BEM. It has been verified that among the two numerical procedures the Cohesive Crack Model gives better results and both give smaller displacements after the rupture.
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Mesure des fonctions de fragmentation des jets et de leurs moments dans les collisions pp à Vs = 2.76 TeV avec ALICE au LHC / Measurement of jet fragmentation functions and of their moments in pp collisions at Vs = 2.76 TeV with ALICE at the LHCWang, Mengliang 10 December 2016 (has links)
Un cross-over entre la matière nucléaire ordinaire et le plasma de quarks et gluons (PQG) est prédit par la QCD sur réseau à bas PB et haute température. Expérimentalement les collisions d'ions lourds ultrarelativistes sont utilisées pour étudier cet état dense et chaud. Produits lors d'un processus dur en début de collision, un parton de grande énergie en perd dans le milieu avant de fragmenter en une gerbe de hadrons appelée jet. Une étude de la modification de la structure et de la fragmentation du jet dans le milieu par rapport au vide permet d'améliorer notre connaissance du PQG. Les fonctions de fragmentation (FF) d'un jet décrivent les distributions en impulsion des hadrons dans ce dernier. Dans les collisions proton-proton (pp), leur mesure est importante pour comprendre les mécanismes de fragmentation de partons. Dans les collisions noyau-noyau, elle permet d'étudier les mécanismes de perte d'énergie. Cependant, la présence d'un important bruit de fond qui fluctue rend la mesure complexe. Il a alors été suggéré de mesurer les moments des FF qui y seraient moins sensibles. Le détecteur ALICE au LHC a des capacités de trajectométrie uniques permettant la mesure des particules chargées jusqu'à des impulsions de 150 MeV/c rendant possible une étude fine de la structure du jet et de ses FF. Les calorimètres électromagnétiques (EMCal et DCal) peuvent aussi être utilisés pour améliorer la mesure de l'énergie du jet. Nous présentons les mesures des FF des jets chargés et les premières études des moments des FF dans les collisions pp à .s=2.76 TeV dans ALICE. Une partie du travail est aussi dédiée à l'implémentation de la géométrie de DCal dans le logiciel d'analyse. / A cross-over between ordinary nuclear matter and a state of deconfined quarks and gluons, the Quark Gluon Plasma (QGP), is predicted by lattice QCD at low PB and high temperature. Experimentally, ultra-relativistic heavy ion collisions are used to produce and to study the hot and dense QGP medium. Produced in a hard scattering at the early stage of the collision a highly energetic parton is expected to lose energy in the medium before fragmenting into a spray of hadrons called jet. A study of the modification of the jet structure and of its fragmentation pattern in medium compared to the vacuum case should provide insights into the QGP properties. The jet fragmentation functions (FF) describe the momentum distribution of hadrons inside a jet. In proton-proton (pp) collisions their measurement is important for understanding the mechanisms of parton fragmentation while it can shed light on the energy loss mechanisms in nucleus-nucleus (AA) collisions. However, the presence of a large fluctuating background in AA makes the measurement a challenging task. The use of FF moments has been proposed to overcome this difficulty. The ALICE detector at the LHC has unique tracking capabilities enabling to measure charged particles down to transverse momenta of 150 MeV/c. This allows assessing possible modifications of the jet structure and FF. The electromagnetic calorimeters (EMCal and DCal) can also be used to improve the measurement of the jet energy. We present the measurements of charged-jet FF and the first studies of FF moments in pp collisions at .s=2.76 TeV in ALICE. Part of the work is also dedicated to the implementation of the DCal geometry in the ALICE offline software.
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